feat(schema): add UNF/NOINDEX field attributes (#374)

Add support for UNF (un-normalized form) and NOINDEX attributes
for schema field classes, following Python RedisVL PR #386.

Features:
- TextField: Add UNF support via Jedis sortableUNF()
- NumericField: Add UNF flag (stored but limited by Jedis)
- NOINDEX: Already supported via indexed=false
- Comprehensive unit tests (16 tests)
- Maintains backward compatibility

Key behaviors:
- UNF only applies when sortable=true
- UNF preserves original character case for sorting
- NOINDEX prevents indexing, field still sortable/retrievable
- TextField & NumericField support both UNF and NOINDEX
- TagField & GeoField support NOINDEX only

Limitations:
- Jedis NumericField doesn't have sortableUNF() yet
- Filed TODO to request Jedis enhancement

Python Reference: redis/redis-vl-python#386

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: bsbodden

core/src/main/java/com/redis/vl/schema/NumericField.java

@@ -10,18 +10,22 @@
 @Getter
 public class NumericField extends BaseField {
 
+  /** Un-normalized form - disable normalization for sorting (only applies when sortable=true) */
+  private final boolean unf;
+
   /**
    * Create a NumericField with just a name.
    *
    * @param name The field name
    */
   public NumericField(String name) {
-    super(name);
+    this(name, null, true, false, false);
   }
 
   /** Create a NumericField with all properties */
-  private NumericField(String name, String alias, Boolean indexed, Boolean sortable) {
+  private NumericField(String name, String alias, Boolean indexed, Boolean sortable, Boolean unf) {
     super(name, alias, indexed != null ? indexed : true, sortable != null ? sortable : false);
+    this.unf = unf != null ? unf : false;
   }
 
   /**
@@ -59,6 +63,9 @@ public SchemaField toJedisSchemaField() {
 
     if (sortable) {
       jedisField.sortable();
+      // NOTE: Jedis NumericField doesn't support sortableUNF() yet
+      // The unf flag is stored in this wrapper but cannot be passed to Redis via Jedis
+      // TODO: File issue with Jedis to add sortableUNF() support for NumericField
     }
 
     if (!indexed) {
@@ -74,6 +81,7 @@ public static class NumericFieldBuilder {
     private String alias;
     private Boolean indexed;
     private Boolean sortable;
+    private Boolean unf;
 
     private NumericFieldBuilder(String name) {
       this.name = name;
@@ -144,6 +152,39 @@ public NumericFieldBuilder sortable() {
       return this;
     }
 
+    /**
+     * Set whether to use un-normalized form for sorting
+     *
+     * <p>UNF disables normalization when sorting, preserving original values. Only applies when
+     * sortable=true.
+     *
+     * <p>NOTE: Jedis doesn't support sortableUNF() for NumericField yet, so this flag is stored but
+     * not passed to Redis.
+     *
+     * @param unf True to disable normalization for sorting
+     * @return This builder for chaining
+     */
+    public NumericFieldBuilder unf(boolean unf) {
+      this.unf = unf;
+      return this;
+    }
+
+    /**
+     * Use un-normalized form for sorting (equivalent to unf(true))
+     *
+     * <p>UNF disables normalization when sorting, preserving original values. Only applies when
+     * sortable=true.
+     *
+     * <p>NOTE: Jedis doesn't support sortableUNF() for NumericField yet, so this flag is stored but
+     * not passed to Redis.
+     *
+     * @return This builder for chaining
+     */
+    public NumericFieldBuilder unf() {
+      this.unf = true;
+      return this;
+    }
+
     /**
      * Build the NumericField instance.
      *
@@ -154,7 +195,7 @@ public NumericField build() {
       if (name == null || name.trim().isEmpty()) {
         throw new IllegalArgumentException("Field name cannot be null or empty");
       }
-      return new NumericField(name, alias, indexed, sortable);
+      return new NumericField(name, alias, indexed, sortable, unf);
     }
   }
 }

core/src/main/java/com/redis/vl/schema/TextField.java

@@ -23,13 +23,17 @@ public class TextField extends BaseField {
   @JsonProperty("phonetic")
   private final String phonetic;
 
+  /** Un-normalized form - disable normalization for sorting (only applies when sortable=true) */
+  @JsonProperty("unf")
+  private final boolean unf;
+
   /**
    * Create a TextField with just a name
    *
    * @param name Field name
    */
   public TextField(String name) {
-    this(name, null, true, false, 1.0, false, null);
+    this(name, null, true, false, 1.0, false, null, false);
   }
 
   /** Create a TextField with all properties */
@@ -40,11 +44,13 @@ private TextField(
       Boolean sortable,
       Double weight,
       Boolean noStem,
-      String phonetic) {
+      String phonetic,
+      Boolean unf) {
     super(name, alias, indexed != null ? indexed : true, sortable != null ? sortable : false);
     this.weight = weight != null ? weight : 1.0;
     this.noStem = noStem != null ? noStem : false;
     this.phonetic = phonetic;
+    this.unf = unf != null ? unf : false;
   }
 
   /**
@@ -80,7 +86,11 @@ public SchemaField toJedisSchemaField() {
       jedisField.as(alias);
     }
 
-    if (sortable) {
+    // Handle sortable with UNF support
+    // UNF only applies when sortable=true
+    if (sortable && unf) {
+      jedisField.sortableUNF();
+    } else if (sortable) {
       jedisField.sortable();
     }
 
@@ -112,6 +122,7 @@ public static class TextFieldBuilder {
     private Double weight;
     private Boolean noStem;
     private String phonetic;
+    private Boolean unf;
 
     private TextFieldBuilder(String name) {
       this.name = name;
@@ -247,6 +258,33 @@ public TextFieldBuilder withPhonetic(String phonetic) {
       return this;
     }
 
+    /**
+     * Set whether to use un-normalized form for sorting
+     *
+     * <p>UNF disables normalization when sorting, preserving original character case. Only applies
+     * when sortable=true.
+     *
+     * @param unf True to disable normalization for sorting
+     * @return This builder
+     */
+    public TextFieldBuilder unf(boolean unf) {
+      this.unf = unf;
+      return this;
+    }
+
+    /**
+     * Use un-normalized form for sorting (equivalent to unf(true))
+     *
+     * <p>UNF disables normalization when sorting, preserving original character case. Only applies
+     * when sortable=true.
+     *
+     * @return This builder
+     */
+    public TextFieldBuilder unf() {
+      this.unf = true;
+      return this;
+    }
+
     /**
      * Build the TextField
      *
@@ -256,7 +294,7 @@ public TextField build() {
       if (name == null || name.trim().isEmpty()) {
         throw new IllegalArgumentException("Field name cannot be null or empty");
       }
-      return new TextField(name, alias, indexed, sortable, weight, noStem, phonetic);
+      return new TextField(name, alias, indexed, sortable, weight, noStem, phonetic, unf);
     }
   }
 }